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%I #6 May 08 2018 13:38:13
%S 1,7,14,33,70,157,346,769,1710,3813,8514,19049,42678,95757,215114,
%T 483793,1089150,2454197,5534546,12490169,28205510,63730653,144073434,
%U 325848609,737262478,1668717957,3778162914,8556569353,19383222230,43918469037
%N Number of nX2 0..1 arrays with every element unequal to 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.
%C Column 2 of A304149.
%H R. H. Hardin, <a href="/A304143/b304143.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +3*a(n-2) -2*a(n-3) -6*a(n-4) -4*a(n-5) for n>6.
%F Empirical g.f: x -x^2*(-7+16*x^2+24*x^3+12*x^4) / ( (2*x-1) *(1+x) *(2*x^3+2*x^2+x-1) ). - _R. J. Mathar_, May 08 2018
%e Some solutions for n=5
%e ..0..1. .0..1. .0..1. .0..0. .0..1. .0..1. .0..1. .0..1. .0..0. .0..1
%e ..1..1. .0..1. .0..1. .1..0. .1..1. .0..0. .1..1. .1..1. .1..1. .1..1
%e ..1..1. .1..0. .0..1. .1..1. .1..1. .1..0. .0..1. .0..0. .1..0. .1..0
%e ..0..1. .1..0. .1..0. .0..0. .0..0. .1..1. .0..0. .0..0. .0..0. .0..0
%e ..0..0. .1..0. .0..1. .0..1. .1..0. .0..1. .1..1. .1..0. .1..1. .1..0
%Y Cf. A304149.
%K nonn
%O 1,2
%A _R. H. Hardin_, May 07 2018